Agronomic Approach to Increase Seed Zinc Content and Productivity of Chickpea (Cicer Arietinum L.) Varieties on Zinc Deficient Soils of Southern Ethiopia

Abstract

Low dietary intake of Zn is the major reason for the prevalence of Zn deficiency in the majority of the population in the Southern Ethiopia. Fertilizer application is one of the agronomic approaches that enhance nutrition quality of grains in addition to its role in raising productivity. Field experiment was conducted in three locations with zinc deficient soils of Southern Ethiopia during 2012 and 2013 cropping seasons to determine zinc fertilizer rate which improve seed zinc content and productivity of chickpea varieties. A factorial combination of three chickpea varieties (Habru, Mastewal and Local) and seven zinc fertilizer rates (0, 5, 10, 15, 20, 25, and 30 kg ZnSO₄.7H₂O ha^-1) were laid in Randomized Complete Block design within three replications. Results revealed that Habru (the improved Kabuli type) was taller (9%) than Mastewal (the improved desi type) and the local landrace. Landrace produced 7% more pods per plant than Habru. Inversely, Habru had 60% heavier seed weight than the landrace. The significant interaction effect of variety by location on grain yield, seed zinc yield and straw zinc content indicated that Mastewal was superior in grain yield at Jolle andegna and Huletegna Choroko, while landrace performed better at Taba. The landrace and Habru were superior in seed zinc yield and straw zinc content across locations, in that order. There was no significant effect of zinc fertilization on agronomic performance of chickpeas. Seed zinc content and seed zinc yield significantly varied among zinc rates.  25 kg ZnSO₄.7H₂O ha^-1 resulted in 7, 8, and 10% more seed zinc and straw zinc content and seed zinc yield over the control, respectively. Therefore, application of 25 kg ZnSO₄.7H₂O with either of the varieties can be recommended for chickpeas zinc enrichment under zinc deficient soil condition of southern Ethiopia.

Keywords: seed zinc, zinc content, zinc deficient, enrichment, micronutrient, agronomic approach